In the food, livestock, breeding animal and domestic animal industry the production of/in breeding and production animals is of great importance to the economy. Hence, there is a demand for agents that increase the productivity by for example improved fertility, more progeny born alive (especially pig, cow and sheep), lower mortality after birth, increased growth during the sucking period, higher milk production, shorter recovery period between weaning and new heat, and generally improved state of health due to strengthened immune defence.
The present invention now provides such an agent, which consists of at least one type of xanthophylles, preferably naturally produced astaxanthin
Astaxanthin belongs to the xanthophylles, which is a large group of carotenoids containing oxygen in the molecule in addition to carbon and hydrogen. The carotenoids are produced de novo by plants, fungi and some bacteria.
Xanthophylles have since long been used in the feed for laying hens and in some parts of the world in the feed for broilers, but not in the feed for breeding or production mammals. The purpose has solely been to pigment the product, the yolk or fat and skin tissue, to satisfy the demands of the consumers. As sources for pigment both naturally produced xanthophylles and synthetically produced ones have been used (Hencken H., 1992, Poultry Science 71:711-717, Karunajeewa H. & A. Hoffman, 1992, Arch fur Geflugeikunde 56(3):109-112).
Thus, it has not previously been known that xanthophylles, and among them astaxanthin, have the ability to increase the production of/in breeding and production mammals.
The reason for the improved productivity when astaxanthin enriched feed is used according to the present invention is not known, but it can be assumed to be due to the antioxidative properties of astaxanthin, and hence the ability to scavenge so-called free radicals. The other xanthophylles do also have antioxidative properties. However, in biological tests astaxanthin has been shown to possess clearly the best antioxidative properties compared to other carotenoids (Miki W., 1991, Pure and Appl Chem 63 (1): 141-146).